Table 1.
V. cholerae regulatory factors and their contributions to colonization of the infant mouse small intestine
| Strain* | Gene† | Putative protein function | Colonization fitness, CI‡ |
|---|---|---|---|
| T1.1 | sltA (VC 0866) | Soluble lytic transglycosylase | 0.18§ |
| T1.5 | prpB (VC 1336) | Carboxyphosphonoenolpyruvate phosphonomutase | 0.49 |
| T2.5 | vps70/capK (VC 0924) | Biofilm-associated exopolysaccharide biosynthesis | 0.58 |
| T2.9 | rtxB (VC 1448) | ABC transporter for RTX toxin | 0.55 |
| T8.5 | cheA-2 (VC 2063) | Chemotaxis sensor kinase | 5.3¶ |
| T10.6 | cheY-3 (VC 2065) | Chemotaxis response regulator | 4.5¶ |
| C2.3 | vieS (VC 1653) | Three-component sensor kinase | 1.32 |
| C3.4 | mfrha (VC 0443) | Mannose/fucose-resistant hemagglutinin | 0.58 |
| C3.5 | cheZ (VC 2064) | CheY phosphatase | 3.5¶ |
| C6.1 | mcpX (VC 2161) | Methyl-accepting chemotaxis protein | 2.2 |
| Site-specific mutations generated | |||
| — | cheA-2H49Q | Autophosphorylation mutant | 92¶ |
| — | cheY-3D52N | Phosphoreceiver mutant | 69¶ |
| — | ΔmotAB | Flagellar motor protein | 0.09§ |
| — | ΔmotY | Flagellar motor protein | 0.03§ |
| — | ΔflaA | Flagellar subunit | 0.07§ |
A strain designation starting with a T or C indicates isolation from the toxT∷tnpR or ctxA∷tnpR fusion strain selection, respectively. The cheA-2 gene was identified by both selections.
The gene name and locus designation (in parentheses) are from the Institute for Genomic Research database of the V. cholerae genome.
The competitive index (CI) was calculated as the mean of the ratios of mutant to wild-type cfu recovered from the small intestines of 5 mice after 24 h of infection. Mutant strains significantly less fit for colonization than wild type (
, P < 0.05), or more fit than wild type (
, P < 0.05) by the Wilcoxon signed ranked sum test are indicated.